Rope socket



Dec. 23, 194i. M 'w. I UKES x-:TAL

ROPE SOCKET Filed' oct. 14, 1938 2 sheets-sheet 1 .A En "Milf Dec. 23,1941. M w. LUKES ETAL 2,266,883

ROPE SOCKET Filed Oct. 14, 1938 2 Sheets-Sheet Patented Dec. 23, 1941UNITED STATES. PATENT orner-.4M

MichaelvW.

Lukesand Stanley G. Davies, Bakersfield,r Calif.

Application October 14, 19738, Serial No. 234,950

(crew- 75) i Claims.

This invention relates to a connecting` or coupling device and relatesmore particularly to a rope socket. A general object of this in-`vention is to provide a simple, practical and dependable rope socket forconnecting a cable or wire rope with a well tool or similar object.

The devices employed to connect wire rope or cable with well drillingtools, and the like, are known in the art as rope sockets. The Vropesockets now in general use are provided With openings for receiving theend portions of the cable or rope. The end portions of the cable or ropearefrayed and babbitt, or the like, is cast in the openings to securethe frayed cable or rope endsrtherein. Such typical rope sockets are notentirely 'dependable and the fraying oi the cable and the pouring of thelead or babbitt are diicult, time consuming operations. LFurther,typical rope sockets are not releasable and the cable must be cut todisconnect it from the tool or object carrying the rope socket.

Another object of this` invention is to provide a dependable rope socketthat may be easily and quickly made up or applied.

Another object of this inventionis to provide a rope socket thatembodies anovel dependable wedge meansfor gripping the cable and doesnot require raying of the cable or thepouring of babbitt or lead.

Another obect of. this invention is .to provide a rope` socket thatmaybe easily .and quickly releasedby merely ybreaking or unthreading athreaded connection. The improved rope socket of .the present inventionsecurely land dependably engages the cable when fully made up and yet.may be easily and quickly released when it is -desired to remove ordisconnect theV cable.

Another objecty of this invention is, to provide a rope socket of thecharacter mentioned. embodying a novel combination of threadedconnections and cablegripping means that effects the automaticconditioning of thegripping means when the socketsections are assembledand that frees the gripping means for. immediate release when thethreaded connection between the socketl sections is broken orunthreaded.

Another object of this invention. is to provide a rope socket embodyingnovel cable ,gripping A further object of this invention is to pro-lvide a rope socket of the character mentioned in which the cablegripping elements have extensive and even engagement with theiractuating wedge surfaces to have even gripping Contact with the cable.

The various objects and features of our invention will be fullyunderstood from the following detailed description of a typicalpreferred form and application of the invention, throughout whichdescription reierence is made to the accompanying drawings, in which:

Fig. 1 isa side elevation of` the improvedrope socket provided by thepresent invention. Fig. 2 is an enlarged longitudinal detailedsectionalview illustrating the principal parts ofthe rope socket in the assembledor active positions.V Fig. 3 is an enlarged transverse detailedsectional View taken as indicated by line 3-#3 on Fig. 2. Fig. 4 is anenlarged fragmentary side View of a typical wire rope or cable. Fig.4 5is an enf larged fragmentary` transverse detailed sectional Viewillustrating the manner in which the gripping elements conform to thecable. Fig. 6 is an enlargedl elevation of the inner side of one of thegripping elements. Fig. 'l is, an enlarged longitudinal detailedsectional view of thevibration resisting cone, and Figs. 8 and 9 arecentral longitudinal detailed sectional views with. certain parts inside elevation illustrating two steps in assembling the. rope socket.

The rope socket of the present invention may be designed for use inconnection with. cables or Wire rope of various characters. In thepresent disclosure we will describe a form of the invention for use witha stranded wirerope o-r cable of a type used in well drilling and wellpumping operations. It is to be understood that the invention is not tobe construed as limited or restricted to the particular form orapplication of the invention abo-ut to be described.

The cable C illustrated in the drawings includes six strands S, eachmade up of a plurality of twisted wire strands or wires W, and a core I0within the series of strands S. The vlay of the strands S is uniform andthe lay of the Wires W is different from the lay of the strands S. Fromvan inspection of Fig. 4 of the drawings it will be seen that theindividual wire strands or wires W are substantially vertical orlongitudinal with respect to the longitudinal axis of the cable at thecrests or outermost surfaces of the strands S. This disposition of thewires W results from the lay of the wires in the spiralled or helicalstrands S. The individual strands or wires W are steel and are subjectto little or no distortion.

The improved rope socket of our present invention may be said tocomprise, generally, two body sections A and B, a threaded connection |Ibetween the sections A and B and cable gripping means I2 conditioned foroperation when the threaded connection I| is made up and released orfreed for release when the threaded connection I I is broken orunthreaded.

The sections A and B constitute the principal body parts of the ropesocket and contain or carry the various other parts of the device. The

body section A is an elongate tubular member" having a centrallongitudinal opening I3. The section A is adapted to be connected with atool or other object. In the construction illustrated a sub orconnecting member I4 serves to connect the body section A with a tool Tor similar object. The connecting member I4 has a pin I5 threaded in thelower end of the tubular body section A and has a socket I6 in its lowerend receiving a threaded pin on the tool T. The exterior of the bodysection A may be cylindrical except for a set or pair of flat faces I1provided for engagement by a wrench or other turning tool.

The body section B is a tubular member having a central longitudinalopening I8. The opening I8 is adapted to pass the cable C with suitableclearance and, as illustrated, is smaller in diameter than the openingI3 of the section A. A head or cap I9 is threaded on the upper endportion of the section B. The cap I9 has a central longitudinal opening28 whose wall slopes downwardly and outwardly. A tubular cone 2| isarranged in the opening 28 and is shaped and proportioned to conform tothe wall of the opening. The lower end of the cone 2| rests on Atheupper end of the body section B. Longitudinally extending cuts or slits22 enter the cone 2| from its opposite ends to make theconecompressible. When the cap I9 is threaded down the wall of itsopening 29 cooperates with the cone 2| to compress the cone into tightengagement with'the cable C. The cone 2| serves to prevent vibration andlplay of the cable C in the opening I8 and is not primarily intended togrip the cable C forthe purpose .of holding the same. l The threadedconnection II between the two body sections A and B may be variedconsiderably without departing from the broader aspects of theinvention. In the construction illustrated the connection II includes apin 23 on the lower end of the body section B threaded in the upper endof the opening I3 in the section A. The threads 24 on the pin 23 and thewall of the opening I3 are preferably of substantial length. In'theconstruction disclosed in the drawings it may be considered that thethreads 24 are right hand threads. A shoulder 25 is provided on thesection B at the upper end of the pin 23 and engages or opposes theupper end of the body section A. v

The cable gripping means I2 is a feature of the invention. The means I2is positive and dependable in preventing the detachment or disconnectionof the cable C and yet is such that it'may be released or freed forready release by merely breaking or disconnecting the above describedthreaded connection II` The cable gripping means I2 includes a tubularshell or cage 26 in the opening I3 of the body section A. The exteriorofthe cage 26 is adapted to have frictional or wedging cooperation withthe wall of the opening I3 in the section A. In accordance with theinvention the wall of the opening I3 slopes or tapers downwardly andinwardly and the exterior of the cage 26 is correspondingly tapered tohave even cooperation with the wall of the tapered opening.

The shell or cage 26 is threadedly connected with the body section B. Asocket 21 is provided in the lower end of the pin 23 and the upperportion of the cage 26 is reduced in diameter and is threaded in thesocket 21. In accordance with the invention the threads 28 on the wallof the socket 21 and on the cage 26 have a pitch opposite to the pitchof the threads 24. Thus where the threads 24 are right hand threads, asabove described, the threads 28 are left hand threads. The cage 26 ispreferably sectional for a purpose which will hereinafter becomeevident. It is preferred to split or divide the cage 21 on radiallongitudinal planes to comprise a plurality of segments or sections 29.In the application of the invention illustrated there are three likesections 29, the cage 26 being split or divided along three longitudinalplanes.

The cage 26 is proportioned to surround the cable C with substantialclearance and the inner side of each cage section 29 has a longitudinalguide-way or groove 38. The grooves 39 of the several cage sections 29are alike. The grooves 30 slope downwardly and outwardly relative to thecentral longitudinal axis of the device. In the preferred constructionthe walls of theV grooves 30 are cylindrically curved, being curvedabout downwardlyY and outwardly inclined axes. It is to be understoodthat the curvature of the walls ofthe grooves 39 is uniform throughoutthe lengths of the grooves, that is, the wall of each groove 3D has asingle radius* of curvature. The inclination of the grooves 30 and theradius of curvature of the walls of the grooves are such that the upperends ofthe three grooves 38 may define a substantiallycylindrical andcomplete opening at the upper end of the cage 26. The guideways orgrooves 3U preferably extend throughout the length of the cage 26.

'Ihe cable gripping means I2 further includes grippingY elements 3| forengaging or gripping the cable C. There is a set or series of similarelements 3| varranged in the cage 26. to surround and grip the cable C.The gripping elements, 3| are received in or cooperate with the grooves30, there being one gripping element 3| cooperating with each groove 30.'I'he gripping elements 3| are elongate members and in practice may beof substantially the same length as the cage 26. The outer sides of theelements 3| are cylindrically curved to conform .to and even- 1y bear inthe grooves 3|) Aof the cage sections 29. The inner sidesof the grippingelements 3| are shaped to conform to the cable C. In accordance with theinvention the inner sides .of the gripping elements 3l are concave andhave series of helically Vpitched grooves 32 for receiving the strands Sof the cable C. The grooves 32 have the same lay or pitch as the strandsS. It is preferred to cast the grooves 32 in the gripping elements 3| togive vthewalls of the grooves a desirable roughness, although thegrooves may be formed in other manners, if desired. n

It is a feature of the invention that the gripping elements 3| areformed of a material sui- Vciently hard to resist excessive distortionand failure and yet capable of deformation by the in-V the elements 3|are in*tightzengagementwith the cable. It has beenl foundpractical toform the gripping elements 3'I of toughbronze', or the like. YAs pointedout above, the wires Ware substantially parallel and. are longitudinallydisposed to the crests of the strandsS and the cooperation of thelongitudinally'disposed'wires W with the walls of the grooves 32prevents turning and threading of the gripping elements-along the cableC. When a tension of substantial magnitude is put on the vcable C thewires'W are depressed or embedded in the walls of the grooves 32 andform indentations or sub-grooves 33. This depression or indentationofthe wires W in the walls of the grooves 32 is best illustrated in Fig.of the drawings. The embedding of the substantially parallelandlongitudinal wires W in the walls of thehelical grooves 3'2 veffectivelyresists relative turning and threading between the gripping elements 3|andthe cable C.

The cable" gripping means l2 further includes spring means for actuatingor for assisting in the actuation of the gripping elements 3|. Asocket34 is provided in the pin I5'of the connecting member I4 and a helicalcompression spring 35 is seated in the socket 34. The spring 35 extendsupwardly beyond the upper end of the pin |5 to engage thev lower ends ofthe gripping elements 3|. The spring 35' urges the elements 3| upwardlyin the tapered or inclined grooves 30 to assist in setting or actuatingthe gripping elements.

In making up or assembling the rope socket of the present invention thewedge-like sections 29 of the cage 26 are assembled to form the cage 26and the upper portion of the cage is threaded in the socket 21. It ispreferred to thread the cage 26 in the socket 21 by hand. The bodysection A is then passed over the cage 26 and threaded on the pin 23 ofthe section B. During the threading of the section A on the pin. 23 thetapered wall of the opening I3 comes in Contact with the taperedexternal surface of the cage 26 and as the upper end of the section Aapproaches the shoulder the frictional engagement between the wall ofthe opening I3 and the cage 26 results in turning of the Cage with thesection A. The right hand rotation of the cage 26 with the section Aresults in loosening and backing o of the threads 28, the

threads 28 being left hand threads. Thus the cage 26 is backed down acertain extent when the threaded connection is made up. The cable C maythen be threaded through the opening I8 to have its end adjacent orbeyond the lower end of the cage 26. The cap I9 and the cone 22 may befree or loose when the cable is threaded into the body section B. Thegripping elements 3| are then assembled and passed upwardly in the cage26 around the cable C` Fig. 9 of the drawings illustrates the grippingelements 3| being arranged in the cage 25. It is to be understood thatthe gripping elements 3| are arranged in their respective grooves 3l) tohave correct engagement with the cable C. The f opening I3 the gripping.elements 3| are urged upwardly in the inclined grooves 3D. Thisofcourse brings the grippingfelements 3 I into tighter grippingengagementwith the cable C. It may be. found` desirable toapply Vormaintain a certain-tensile strain on the cable C when the grippingelements 3|' are forced into gripping contact with the cable by thecompressed spring 35. When the pin I5 has been fully threaded in thelower end of the opening I3 theY spring 35 exerts a substantial upwardforce on the gripping elements 3|f and the elements obtain a rmengagement with the cable C. A tensile strain is then put on the cable Cand the rope socket assembly and the contact of the elements 3| with thecable urges or feeds the gripping elements along the inclined grooves 30until the gripping elements have a very secure hold on the cable C.

The wedging of the gripping elements 3| against the cable C by themovement of the gripping elements in the inclined grooves 33 results inthe formation of the depressions or sub-grooves 33 in the walls of thehelical grooves 32. As pointed out above, the engagement of thesubstantially parallel crest portions of the wires W with the Vwallsofthe grooves 32 during and subsequent to` the Vformation of thedepressions or grooves 337 prevents backing down or threading 'of theelements 3=I along the cable C. Following the final setting ofthegripping elements 3| by the application of the tensile strain the ropesocket isv in` condition-for use.

When it becomes desirable or necessary torelease the rope socket thebody section A is unthreaded from the section B, that is, the threadedconnection II is broken or unthreaded. The section A- is slid olf' oftheV cage 25 or removed from the cage. The removal of the section A isaccompanied by disengagement of the spring 35 from the lowerr endsv ofthe gripping elements 3|. During the breaking or unthreading of theconnection II the frictional contact of the cage 26 with the Wall of theopening I3 causes the cage to turn with the section A. Owing to the factthat the threads 28 are left hand threads and the threads 24 are righthand threads, rotation of the cage 26 with the section A duringunthreading of the section A results in tightening or threading down ofthe threads 28. In other words the cage 26 is threaded upwardly in thesocket 21 while the section A is threaded downwardly from the section B.The taper on the wall of the opening I3 and the exterior of the cage 29is opposite in direction to the inclination of the grooves 3l] and theexteriors of the gripping elements 3| and when the section A is removed,as just described, the sections 29 of the cage 25 free themselves fromthe gripping elements 3|. The upward threading of the cage 26 .merelythreads the cage to the position where it was threaded by hand when thedevice was assembled and the cage may be easily unthreaded by hand or bymeans of a suitable tool, and the cage and elements 3l may be easilyremoved from the cable C. The cable C may then be withdrawn from theopening I8.

It is to be observed that the slips 3| of the rope socket firmly anddependably grip the cable C to positively prevent detachment ofdisconnection of the cable when the same is under tension. The ropesocket may be easily and quickly released by merely breaking orunthreading the threaded connection II, which operation is accompaniedby the automatic freeing of the 'cage 26 and the freeing ofthe 3|.

, Having described only a typical preferred form and application of ourinvention, we do not wish to be limited or restricted to the speciiicdetails herein set forth, but wish to reserve to ourselves anyvariations or modications that may appear to those skilled in the yartor fall within the scope of the following claims.

Having described our invention, we claim:

1. A coupling device for a cable comprising two sections adapted toreceive the cable, a threaded connection between the sections, means inthe sections for gripping the cable including a cage frictionallybearing in one section, and cable gripping elements held active by thecage, and a threaded connection between the cage and the other section,the threads of said connections being pitched in opposite directionswhereb-y the making up of the first named connection conditions the cageto hold the elements active and the unthreading of said first namedconnection frees the cage to release the elements.

2. A coupling device for a cable comprising two sections adapted toreceive thecable, a threaded connection between the sections, means inthe sections for gripping the cable including elements for gripping thecable, a wedge member frictionally bearing in one section and confiningthe gripping elements about the cable, and a threaded connection betweenthe wedge member and the other section having threads pitched in theopposite direction to the threads of the iirst named connection wherebyrotation of the wedge member with the rst named section duringunthreading of the iirst named connection retracts the wedge member andfrees the gripping ele ments.

3. In a coupling device for a cable, a body section having an openingreceiving the cable, a removable cage bearing in the opening `anddivided gripping elements longitudinally into sections, each sectionhaving an inclined guideway in its inner side, said guideways havingcylindrically curved walls, and gripping elements for gripping the cableand having cylndrically curved rear sides slidably bearing in theguideways.

4. A rope socket for a cable comprising two tubular sections forreceiving the cable, a releasable threaded connection between thesections, an inclined wall on the interior of one section, a cage insaid section having an inclined surface cooperating with the surface ofsaid section, the cage being longitudinally divided into sections, eachcage section having a. groove in its inner side inclined in the oppositedirection to said surfaces and having a cylindrically curved wall,gripping elements having their outer sides conforming to and shiftablein the grooves and having their inner sides shaped to conform to andgrip the cable, and threads connecting the cage with the other sectionand pitched in the opposite direction to the threads of said threadedconnection whereby the frictional engagement of said surfaces causes thecage to thread back and release the gripping elements when the saidthreaded connection is unthreaded.

5. A coupling device for a cable comprising two sections adapted toreceive the cable, a threaded connection between the sections, means inthe sections for gripping the cable including a part frictionallybearing in one section, said section having a tapered socket, a splitcone bearing in said socket and engaging about the cable to dampenvibration, and a threaded connection between said part and the othersection, the threads cf said threaded connections being pitched inopposite directions whereby unthreading of' the rst named connectionthreads said part to release said means.

MICHAEL W. LUKES. STANLEY G. DAVIES.

